Harvesting Energy from Glucose CELLULAR RESPIRATION Harvesting Energy from Glucose

What is Aerobic Cellular Respiration?? This is the process our cells go through to obtain energy from our primary source, glucose Glucose is broken down with the help of oxygen and ultimately produces water, carbon dioxide and energy in the form of ATP and heat C6H12O6 + 6O2  6CO2 + 6H2O + Energy Occurs in the cytoplasm and mitochondrion

The Mitochondrion Each mitochondrion contains an outer an inner membrane, seperated by an intermembrane space. The inner membrane is thrown into curtain-like folds that project inward, dubbed the cristae. Withinn the walls fo the ristae is the matrix that harbors the mitochondrian DNA ribosoomes and ATP synthase particles. Most cells in the human body, with the exception of erythrocytes contain hundreds of mitochondria. Teach mitochondrion contains approximately 10 mnDNA strands.

Overview of Cellular Respiration Stage 1: Glycolysis 10 step process occurring in the cytoplasm Stage 2: Pyruvate Oxidation 1 step process occurring in the matrix Stage 3: Krebs Cycle 8 step cyclical process occurring in the matrix Stage 4: ETC and Chemiosmosis A multi-step process occurring in the inner membrane Good people keep eating cake

Energy Products and Carriers Energy Storage: ATP: Adenosine triphosphate ADP + P + Energy  ATP Energy Carriers: NADH: Nicotinamide adenine dinucleotide NAD+ + H+ + 2e  NADH FADH2: Flavin adenine dinucleotide FAD + 2H+ + 2e  FADH2

Where it Happens

The Role of ATP According to the first law of thermodynamics, energy cannot be created or destroyed, only changed from one form to another or from one object to another The goal of cellular respiration, is to capture as much of the available free energy as possible from the breakdown of glucose, and trap it in the form of ATP The stored energy in ATP can then be used to power reactions in the body, when it is dephosphorylated

ATP Production Substrate – Level Phosphorylation: ATP is made when an enzyme adds a free phosphate group to ADP Oxidative Phosphorylation: When ATP is made using a proton gradient that has been generated through redox reactions

Stage 1: Glycolysis Glucose is broken down in the cytoplasm to produce two 3-carbon pyruvate molecules (anaerobic process) It occurs in ten steps, each one catalyzed by a specific enzyme

The Details 2 ATP are required to kick start the process Fructose diphosphate seperates into 2 molecules  2 paths 2 NADH molecules are made 4 ATP are made in later stages (2 ATP NET) NOTE: PGAL = phosphoglyceraldehyde (Glyceraldehyde-3 phosphate)

References Nelson 12 Biology textbook (pages 94 – 100) http://www.accessexcellence.org/RC/VL/GG/ecb/ATP_ADP.html www.unitedstreaming.com